There is a gun pointed at all of human space and it is in the hands of a madman. The ancient Star Engine, a colossal construct of unknown power, is in the hands of a manipulating schemer. He has already used it once to strike at his enemies, wiping out two entire fleets without giving them the opportunity to fight back. To make matters worse, he has hundreds of thousands of thousands of hostages: men and women he has kidnapped, so that he can mentally program them to do his bidding. The United Colonies Fleet has to stop him. Emperor Lucius Giovanni has a plan. He has an ally, too. His sister, Lieutenant Alanis Giovanni, is on the surface of the Star Engine, and she plans to take the construct and free the prisoners. If she can do that, then Lucius might have a chance in seizing the system without losing entire fleets. First, though, Lucius has to deal with the treacherous Centauri Confederation, which seems bent upon destroying the new nation he has built, deal with unknown aliens who kill without explanation or remorse, and protect the worlds of the United Colonies. The fate of human space and possibly far more rests upon who controls the Star Engine.